Flash, although better for compatibilties sake, is a pain to work with.

Rodent Rush has about 10 different gameplay tunes to keep it interesting, and in the original Vitalize version of the game I was able to use something called "modules" to load the music.

Module music files are fairly small becaue they are modular. Each song file stores only the sounds used in the song and in what order to play them.

Well flash doesn't support module music natively (not built-in), so instead of writing a engine to read them I decided to just convert all the songs to FLV's and steam them, much like how YouTube handles their videos.